1. Field of the Invention
This invention relates to a process for preparing a ball-point pen ink.
2. Description of the Prior Art
Solutions of cationic-anionic dye salts are useful as ball-point pen inks. Prior art processes for preparing solvent-soluble forms of cationic-anionic dyes include those which are carried out combining one or more anionic dyes in aqueous solution with one or more cationic dyes in aqueous solution, the anionic and cationic dyes being present in approximately stoichiometric amounts. Coprecipitation occurs, yielding an amorphous salt-like combination of the anionic and cationic dye components. The precipitate is isolated and, after drying, is dissolved in a suitable ball-point pen ink solvent, e.g., an alcohol, glycol or glycol ether.